Therapeutic Effects of Hydrogen Gas Inhalation on Trimethyltin-Induced Neurotoxicity and Cognitive Impairment in the C57BL/6 Mice Model

Myricetin alleviates learning and memory deficits in trimethyltin Alzheimer's phenotype via attenuating hippocampal endoplasmic reticulum stress and regulating inflammation and oxidative stress

Trimethyltin hydrochloride (TMT) induces hippocampal neurodegeneration and learning and memory impairments, providing a useful experimental model for Alzheimer's disease (AD) research. This study aimed to explore the neuroprotective effects of myricetin, a naturally occurring flavonoid with antioxidant and anti-inflammatory properties, against TMT-induced hippocampal damage and elucidate some of its underlying molecular mechanisms. Male NMRI mice (n = 32) were divided into four experimental groups: control, control + myricetin, TMT, and TMT + myricetin. Neurodegeneration was induced by intraperitoneal TMT injection (2.8 mg/kg), followed by daily oral administration of myricetin (25 mg/kg) for 21 days. Learning and memory-related function was assessed using passive avoidance, novel object recognition, and Y-maze tests. After behavioral tasks, hippocampal levels of oxidative stress parameters (glutathione (GSH), superoxide dismutase (SOD), catalase, malondialdehyde (MDA)), inflammatory markers (tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10)), and endoplasmic reticulum stress pathway proteins (GRP78, PERK, IRE1α, and CHOP) were evaluated. Histological examinations included Nissl staining to quantify neuronal degeneration in CA1 and dentate gyrus regions, as well as glial fibrillary acidic protein (GFAP) immunohistochemistry. Myricetin treatment attenuated TMT-induced learning and memory impairments and neuronal loss in the CA1 and dentate gyrus subfields. It significantly enhanced hippocampal levels of GSH, SOD and catalase activities, and IL-10 while reducing levels of MDA, TNF-α, and GFAP immunoreactivity. Moreover, myricetin alleviated the TMT-induced elevation of GRP78, PERK, IRE1α, and CHOP. These findings suggest that myricetin holds promise as a therapeutic candidate for AD and other neurodegenerative disorders by counteracting oxidative stress, suppressing neuroinflammation, and modulating endoplasmic reticulum stress pathways.

Hydrogen inhalation exerts anti-seizure effects by preventing oxidative stress and inflammation in the hippocampus in a rat model of kainic acid-induced seizures

Hydrogen gas (H2) is an antioxidant with demonstrated neuroprotective efficacy. In this study, we administered H2 via inhalation to rats to evaluate its effects on seizures induced by kainic acid (KA) injection and the underlying mechanism. The animals were intraperitoneally injected with KA (15 mg/kg) to induce seizures. H2 was inhaled 2 h once a day for 5 days before KA administration. The seizure activity was evaluated using Racine's convulsion scale and electroencephalography (EEG). Neuronal cell loss, glial cell activation, and the levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, CCL2, and CCL3), reactive oxygen species (ROS) and nuclear factor erythroid 2-related factor 2 (Nrf2) in the hippocampus were assessed. The cerebral blood flow of the rats was also evaluated. The results revealed that KA-treated rats presented increased seizure intensity; increased neuronal loss and astrocyte activation; increased levels of ROS, TNF-α, IL-1β, IL-6, CCL2, and CCL3; and reduced Nrf2 phosphorylation levels. Pretreatment with H2 inhalation significantly attenuated seizure intensity; prevented neuronal loss; decreased microglial and astrocytic activation; decreased ROS, TNF-α, IL-1β, IL-6, CCL2 and CCL3 levels; and increased Nrf2 levels. Inhalation of H2 also prevented the KA-induced decrease in cerebral blood flow. These results suggest that pretreatment with H2 inhalation ameliorates KA-induced seizures and inhibits the inflammatory response and oxidative stress, which protects neurons.

Synergistic Antioxidant Effects of Molecular Hydrogen and Cold Atmospheric Plasma in Enhancing Mesenchymal Stem Cell Therapy

In regenerative medicine, mesenchymal stem cells (MSCs) have shown their importance and potential in tissue reconstruction and immune system modification. However, such cells' potential is often diminished by factors such as oxidative stress, immune rejection, and inadequate engraftment. This review highlights the role of molecular hydrogen (H2) and cold atmospheric plasma (CAP) as adjunct therapies to improve the effectiveness of MSC therapy. H2 has strong antioxidative and anti-inflammatory actions as it quenches reactive oxygen species and positively stimulates the Nrf2 pathway that promotes MSC survival and life. CAP, being a modulated source of ROS and RNS, also assists MSCs by altering the cellular redox balance, thus facilitating cellular adaptation, migration, and differentiation. H2 and CAP in conjunction with each other assist in establishing an ambience favorable for promoting MSCs' survival and growth abilities, and reduce the healing time in various pathways such as wound, neuroprotection, and ischemia. Besides these concerns, this review also covers the best administration routes and doses of H2 and CAP together with MSCs in therapy. This study informs on a novel dual method aimed at improving the outcome of MSC therapy while adding several molecular targets and relevant clinical uses concerning these therapies. Research of the future has to deal with bettering these protocols so that the therapeutic benefits can be maximized without long-term implications for clinical applications.

Hydrogen Gas Inhalation Alleviates Airway Inflammation and Oxidative Stress on Ovalbumin-Induced Asthmatic BALB/c Mouse Model

Airway inflammatory diseases, such as asthma, are a global public health concern owing to their chronic inflammatory effects on the respiratory mucosa. Molecular hydrogen (H2) has recently been recognized for its antioxidant and anti-inflammatory properties. In this study, we examined the therapeutic potential of H2 in airway inflammation using an ovalbumin (OVA)-induced BALB/c mouse model of allergic asthma. Female BALB/c mice were sensitized and challenged with OVA to induce airway inflammation, and 30 mice were randomly divided into five groups: NT (non-treatment), HTC (3% H2 treatment only), NC (negative control, OVA only), PC (positive control, OVA + intranasal 1 mg/mL salbutamol 50 μL), and HT (H2 treatment, OVA + inhaled 3% H2). Various inflammatory and oxidative stress (OS)-induced markers such as white blood cells (WBCs) and their differential counts, lung histology, cytokine levels such as interleukin (IL)-4, (IL)-5, (IL)-13, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), granulocyte-macrophage colony-stimulating factor (GM-CSF), (IL)-10, reactive oxygen species (ROS), nitric oxide (NO), glutathione peroxidase (GPx), and catalase (CAT), and total immunoglobulin E (IgE) levels were investigated. Our results showed that inhaled H2 significantly reduced inflammatory cell infiltration, OS markers, and pro-inflammatory cytokine expression while upregulating antioxidant enzyme activity. Furthermore, H2 also significantly decreased serum IgE levels, a marker of allergic inflammation. Collectively, our findings suggest that H2 inhalation is a promising treatment option for airway inflammation, offering a novel approach with potential clinical applications.

Beta-sitosterol mitigates cognitive deficit and hippocampal neurodegeneration in mice with trimethyltin-induced toxicity

The present study investigated the neural health benefit of beta-sitosterol (BSS) against trimethyltin (TMT)-induced neurodegeneration in mice. Forty male Institute of Cancer Research (ICR) mice were randomly divided into Sham-veh, TMT-veh, TMT-BSS50, and TMT-BSS100. A one-time intraperitoneal injection of 2.6 mg/kg of TMT was given to mice in TMT groups. Vehicle (veh), BSS 50 mg/kg or BSS 100 mg/kg were orally given for 2 weeks. Spatial learning and memory were evaluated. Brain oxidative status, hippocampal neuropathology, and reactive astrocytes were done. White matter pathology was also evaluated. The results indicated the massy effect of TMT on induced motor ability and spatial memory deficits in accordance with increased neuronal degeneration in Cornus ammonis (CA) 1, CA3, and dentate gyrus (DG) and internal capsule white matter damage. TMT also induced the reduction of reactive astrocytes in CA1 and DG. Brain's catalase activity was significantly reduced by TMT, but not in mice with BSS treatments. Both doses of BSS treatment exhibited improvement in motor ability and spatial memory deficits in accordance with the activation of reactive astrocytes in CA1, CA3, and DG. However, they successfully prevented the increase of neuronal degeneration in CA1 found only with the BSS dose of 100 mg/kg, and it was indicated as the effective dose for neuroprotection in the vulnerable brain area. This study demonstrated mitigative effects of BSS against motor ability and memory deficits with neural health benefits, including a protective effect against CA1 neurodegeneration and a nurturing effect on hippocampal reactive astrocytes.

Neuroprotective Effect of Ixeris dentata Extract on Trimethyltin-Induced Memory Impairment in Rats

Alzheimer's disease (AD) is a representative neurodegenerative disease characterized by the structural and functional degeneration of neurons. The present study investigated the neuroprotective effect of Ixeris dentata (ID) extract on trimethyltin (TMT)-induced memory deficit in the rat. Cognitive improving effect and neuronal activity of ID were assessed by using Morris water maze (MWM) test and choline acetyltransferase (ChAT), cAMP-response element-binding protein (CREB) immunohistochemistry. Seven days after TMT injection (8.0 mg/kg, i.p.), each group of rats was administered saline, water extract of ID (WID, 400 or 800 mg/kg, p.o.), ethanol extract of ID (EID, 400 or 800 mg/kg, p.o.), or caffeic acid (CAF, 30 mg/kg, i.p.) daily for fourteen days. Results: Treatment with EID and CAF produced a significant improvement in escape latency time of the acquisition, and retention time in the target area of the MWM task. Additionally, administration of EID or CAF markedly alleviated TMT-induced loss of ChAT- and CREB-immunoreactive cells in the hippocampus. The results demonstrated that EID has a protective effect against TMT-induced memory deficit, partly through increasing the CREB and cholinergic signaling pathway in the hippocampus. These results suggest that ethanol extracts of ID might be useful for improving cognitive functions in neurodegenerative diseases such as Alzheimer's disease.

Molecular hydrogen supplementation in mice ameliorates lipopolysaccharide-induced loss of interest

Aim

The objective of this study was to evaluate the potential of hydrogen in preventing and treating psychiatric symptoms, particularly depressed mood and loss of interest, and to explore its underlying mechanisms. A mouse model exhibiting inflammation-derived depressive symptoms was used for the investigation.

Methods

Institute of Cancer Research mice were subjected to a 7-day intervention of either 30% hydrogen or 40 g per day of air via jelly intake. On the final day, lipopolysaccharide (LPS) was intraperitoneally administered at 5 mg/kg to induce inflammation-related depressive symptoms. Behavioral and biochemical assessments were conducted 24 h post-LPS administration.

Results

Following LPS administration, a decrease in spontaneous behavior was observed; however, this effect was mitigated in the group treated with hydrogen. The social interaction test revealed a significant reduction in interactions with unfamiliar mice in the LPS-treated group, whereas the hydrogen-treated group exhibited no such decrease. No significant changes were noted in the forced-swim test for either group. Additionally, the administration of LPS in the hydrogen group did not result in a decrease in zonula occludens-1, a biochemical marker associated with barrier function at the cerebrovascular barrier and expressed in tight junctions.

Conclusion

Hydrogen administration demonstrated a preventive effect against the LPS-induced loss of interest, suggesting a potential role in symptom prevention. However, it did not exhibit a suppressive effect on depressive symptoms in this particular model. These findings highlight the nuanced impact of hydrogen in the context of inflammation-induced psychiatric symptoms, indicating potential avenues for further exploration and research.

The role of hydrogen therapy in Alzheimer's disease management: Insights into mechanisms, administration routes, and future challenges

Alzheimer's disease (AD) is a progressive neurodegenerative disorder predominantly affecting the elderly. While conventional pharmacological therapies remain the primary treatment for AD, their efficacy is limited effectiveness and often associated with significant side effects. This underscores the urgent need to explore alternative, non-pharmacological interventions. Oxidative stress has been identified as a central player in AD pathology, influencing various aspects including amyloid-beta metabolism, tau phosphorylation, autophagy, neuroinflammation, mitochondrial dysfunction, and synaptic dysfunction. Among the emerging non-drug approaches, hydrogen therapy has garnered attention for its potential in mitigating these pathological conditions. This review provides a comprehensively overview of the therapeutic potential of hydrogen in AD. We delve into its mechanisms of action, administration routes, and discuss the current challenges and future prospects, with the aim of providing valuable insights to facilitate the clinical application of hydrogen-based therapies in AD management.

Low-dose lithium adjunct to atypical antipsychotic treatment nearly improved cognitive impairment, deteriorated the gray-matter volume, and decreased the interleukin-6 level in drug-naive patients with first schizophrenia symptoms: a follow-up pilot study

This study was conducted to investigate the effects of long-term low-dose lithium adjunct to antipsychotic agent use on the cognitive performance, whole-brain gray-matter volume (GMV), and interleukin-6 (IL-6) level in drug-naive patients with first-episode schizophrenia, and to examine relationships among these factors. In this double-blind randomized controlled study, 50 drug-naive patients with first-episode schizophrenia each took low-dose (250 mg/day) lithium and placebo (of the same shape and taste) adjunct to antipsychotic agents (mean, 644.70 ± 105.58 and 677.00 ± 143.33 mg/day chlorpromazine equivalent, respectively) for 24 weeks. At baseline and after treatment completion, the MATRICS Consensus Cognitive Battery (MCCB) was used to assess cognitive performance, 3-T magnetic resonance imaging was performed to assess structural brain alterations, and serum IL-6 levels were quantified by immunoassay. Treatment effects were assessed within and between patient groups. Relationships among cognitive performance, whole-brain GMVs, and the IL-6 level were investigated by partial correlation analysis. Relative to baseline, patients in the lithium group showed improved working memory, verbal learning, processing speed, and reasoning/problem solving after 24 weeks of treatment; those in the placebo group showed only improved working memory and verbal learning. The composite MCCB score did not differ significantly between groups. The whole-brain GMV reduction was significantly lesser in the lithium group than in the placebo group (0.46% vs. 1.03%; P < 0.001). The GMV and IL-6 reduction ratios correlated with each other in both groups (r = -0.17, P = 0.025). In the lithium group, the whole-brain GMV reduction ratio correlated with the working memory improvement ratio (r = -0.15, P = 0.030) and processing speed (r = -0.14, P = 0.036); the IL-6 reduction ratio correlated with the working memory (r = -0.21, P = 0.043) and verbal learning (r = -0.30, P = 0.031) improvement ratios. In the placebo group, the whole-brain GMV reduction ratio correlated only with the working memory improvement ratio (r = -0.24, P = 0.019); the IL-6 reduction ratio correlated with the working memory (r = -0.17, P = 0.022) and verbal learning (r = -0.15, P = 0.011) improvement ratios. Both treatments implemented in this study nearly improved the cognitive performance of patients with schizophrenia; relative to placebo, low-dose lithium had slightly greater effects on several aspects of cognition. The patterns of correlation among GMV reduction, IL-6 reduction, and cognitive performance improvement differed between groups.

Benefits of Erinacines from Different Cultivate Formulas on Cognitive Deficits and Anxiety-Like Behaviour in Mice with Trimethyltin-Induced Toxicity

We investigated the neurological effects of the varied erinacine composition of different mycelia cultures in mice with trimethyltin (TMT)-induced neurodegeneration. Forty male ICR mice were randomly divided into five groups of Sham-veh, TMT-veh, TMT-EME, TMT-EMR and TMT-EME/R. The TMT groups received 2.6 mg/kg one-time intraperitoneal injections of TMT. Oral dosages of 200 mg/kg erinacine combination from each Hericium erinaceus mycelia (EM) cultivated formula (100% eucalyptus wood [E], 100% rubber wood [R], or 40% eucalyptus wood/60% rubber wood [E/R]) were given for two weeks. Spatial learning, memory, flexibility, and anxious behaviour were evaluated alongside brain tissues' oxidative status and histological analyses. Erinacine composition from EME/R exhibited significant positive effects on spatial learning, memory, flexibility, and anxiety (p < 0.05). These findings emerged concurrently with the significant mitigation of hippocampal lipid peroxidation, CA1 hippocampal, cortical neuron, and corpus callosum white matter degeneration (p < 0.05). These neurological benefits were associated with the EME/R composition of erinacine A, C, D, G, H, I, K and R. The best neuroprotective effect against TMT-induced neurodegeneration in mice is offered by the EME/R erinacine composition according to its anti-lipid peroxidation, its nurturing effect on neuronal and white matter, and mitigation of behavioural deficits.

Effects of Hydrogen Gas Inhalation on Community-Dwelling Adults of Various Ages: A Single-Arm, Open-Label, Prospective Clinical Trial

Molecular hydrogen (H₂) is a versatile therapeutic agent. H₂ gas inhalation is reportedly safe and has a positive impact on a range of illnesses, including Alzheimer's disease (AD). Herein, we investigated the effects of 4 weeks of H₂ gas inhalation on community-dwelling adults of various ages. Fifty-four participants, including those who dropped out (5%), were screened and enrolled. The selected participants were treated as a single group without randomization. We evaluated the association between total and differential white blood cell (WBC) counts and AD risk at individual levels after 4 weeks of H₂ gas inhalation treatment. The total and differential WBC counts were not adversely affected after H₂ gas inhalation, indicating that it was safe and well tolerated. Investigation of oxidative stress markers such as reactive oxygen species and nitric oxide showed that their levels decreased post-treatment. Furthermore, evaluation of dementia-related biomarkers, such as beta-site APP cleaving enzyme 1 (BACE-1), amyloid beta (Aβ), brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor A (VEGF-A), T-tau, monocyte chemotactic protein-1 (MCP-1), and inflammatory cytokines (interleukin-6), showed that their cognitive condition significantly improved after treatment, in most cases. Collectively, our results indicate that H₂ gas inhalation may be a good candidate for improving AD with cognitive dysfunction in community-dwelling adults of different ages.

Sinomenine Attenuates Trimethyltin-Induced Cognitive Decline via Targeting Hippocampal Oxidative Stress and Neuroinflammation

Sinomenine is the main bioactive ingredient of the medicinal plant Sinomenium acutum with neuroprotective potential. This study was designed to assess beneficial effect of sinomenine in alleviation of trimethyltin (TMT)-induced cognitive dysfunction. TMT was administered i.p. (8 mg/kg, once) and sinomenine was daily given p.o. 1 h after TMT for 3 weeks at doses of 25 or 100 mg/kg. Cognitive performance was assessed in various behavioral tests. In addition, oxidative stress- and inflammation-associated factors were measured and histochemical evaluation of the hippocampus was conducted. Sinomenine at a dose of 100 mg/kg significantly and partially increased discrimination index in novel object recognition (NOR), improved alternation in short-term Y maze, increased step-through latency in passive avoidance paradigm, and also reduced probe trial errors and latency in the Barnes maze task. Moreover, sinomenine somewhat prevented inappropriate hippocampal changes of malondialdehyde (MDA), reactive oxygen species (ROS), protein carbonyl, nitrite, superoxide dismutase (SOD), tumor necrosis factor α (TNFα), interleukin 6 (IL 6), acetylcholinesterase (AChE) activity, beta secretase 1 (BACE 1) activity, and mitochondrial membrane potential (MMP) with no significant effect on glutathione (GSH), catalase, glutathione reductase, glutathione peroxidase, and myeloperoxidase (MPO). In addition, lower reactivity (IRA) for glial fibrillary acidic protein (GFAP) as an index of astrocyte activity was observed and loss of CA1 pyramidal neurons was attenuated following sinomenine treatment. This study demonstrated that sinomenine could lessen TMT-induced cognitive dysfunction which is partly due to its attenuation of hippocampal oxidative stress and neuroinflammation.

Explore the Mechanism of β-Asarone on Improving Cognitive Dysfunction in Rats with Diabetic Encephalopathy

Background: The number of people with diabetes is increasing, and many patients have significantly impaired cognitive function. For patients with diabetic encephalopathy (DE), simply lowering blood sugar does not improve learning and memory. Studies have shown that β-asarone can significantly improve cognitive impairment in patients with DE, but the specific mechanism of action is unclear. Objective: This experiment hopes to use a variety of experimental methods to clarify the protective effect and mechanism of β-asarone on brain neurons during the development of DE disease. Methods: A high-sugar and high-fat diet and streptozotocin injection-induced DE rat model was used. β-asarone was administered for four weeks. The experiment used the Morris water maze test, biochemical index detection, and many methods to evaluate the neuroprotective effect of β-asarone on DE rats from various aspects and understand its mechanism. Results: β-asarone reduced neuronal cell damage and significantly improved the learning and memory ability of DE rats. In addition, β-asarone can reduce the oxidative stress response and amyloid-β accumulation in the brain of DE model rats and increase the content of brain-derived neurotrophic factor (BDNF) in the brain tissue, thereby reducing neuronal cell apoptosis and playing a protective role. Conclusion: β-asarone can reduce the accumulation of oxidative stress and amyloid-β in the brain, increase the content of BDNF, reduce the apoptosis of neuronal cells, and exert neuronal protection, thereby improving the learning and memory ability of DE model rats.

CNS Redox Homeostasis and Dysfunction in Neurodegenerative Diseases

A single paragraph of about 200 words maximum. Neurodegenerative diseases (ND), such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis, pose a global challenge in the aging population due to the lack of treatments for their cure. Despite various disease-specific clinical symptoms, ND have some fundamental common pathological mechanisms involving oxidative stress and neuroinflammation. The present review focuses on the major causes of central nervous system (CNS) redox homeostasis imbalance comprising mitochondrial dysfunction and endoplasmic reticulum (ER) stress. Mitochondrial disturbances, leading to reduced mitochondrial function and elevated reactive oxygen species (ROS) production, are thought to be a major contributor to the pathogenesis of ND. ER dysfunction has been implicated in ND in which protein misfolding evidently causes ER stress. The consequences of ER stress ranges from an increase in ROS production to altered calcium efflux and proinflammatory signaling in glial cells. Both pathological pathways have links to ferroptotic cell death, which has been implicated to play an important role in ND. Pharmacological targeting of these pathological pathways may help alleviate or slow down neurodegeneration.